Question

which of the following is not a common problem with gas piping?
threaded connections
leaks
rusting
no drip leg
missing shutoff valves
question 18
1 pts
a tempering valve may be needed on a combination domestic hot water and space heating system. the tempering valve
mixes cool water with the hot water before sending the water to a fan coil
raises the temperature of the domestic hot water delivered to the house
reduces the temperature of the water to the domestic hot water side
never requires a backflow preventer
protects people from scalding when bleeding radiators or radiant piping systems

Explanation:

For the first question, threaded connections are a type of connection method and not a problem. Leaks, rusting, lack of drip - leg, and missing shutoff valves are common issues with gas piping. For the second question, a tempering valve in a combination domestic hot water and space heating system reduces the temperature of the water on the domestic hot water side to prevent scalding.

Answer:

First question: threaded connections
Second question: reduces the temperature of the water to the domestic hot water side